1. Field of the Invention
The present invention relates to a pedometer for measuring a number of steps by detecting walking or running of the human body, particularly relates to a pedometer having a step number measuring function in walking and in running.
2. Description of the Related Art
In a background art, a pedometer capable of measuring the number of steps in walking and in running has been developed.
For example, according to JP-A-2004-101346 (paragraphs through [0032], FIG. 4 through FIG. 6) and JP-A-2005-283340 (paragraphs [0023] through [0040], FIG. 1 through FIG. 4), a walking vibration is detected by a piezoelectric element included in a main body of a wristwatch and a number of steps is counted by amplifying a signal necessary for detecting walking by an amplifying circuit and a filter circuit.
However, a characteristic of the filter circuit is optimized for measuring the number of steps in walking, and therefore, in running, not a signal by a landing impact but only a signal of arm swinging can be detected to pose a problem that a number of steps in running cannot be measured accurately.
JP-A-5-142363 (paragraphs [0008] through [0016], FIG. 1, FIG. 2) discloses an invention disclosing a radio wave correcting timepiece for detecting a radio wave having a previously set frequency and the strongest electric field by switching a tuning circuit and a selecting circuit for correcting time based on time information included in the detected radio wave, and a filter circuit is switched in accordance with the received radio wave. However, Patent Reference 3 does not describe a correlation in the pedometer for measuring walking or measuring running, and therefore, Patent Reference 3 cannot simply be applied to a pedometer.
On the other hand, Japanese Patent Publication No. 2712269 (page 3 through page 4, FIG. 4 through FIG. 6), JP-A-8-77322 (paragraphs [0011] through [0023], FIG. 9, FIG. 13) and JP-A-7-144039 (paragraphs [0013] through [0016], FIG. 1, FIG. 3) disclose an invention for measuring the step of numbers by detecting a plurality of moving motions of walking, running and the like. However, the invention described in Japanese Patent Publication No. 2712269, JP-A-8-77322 and JP-A-7-144039 is provided with only a function of simply controlling a gain of an amplifying circuit in accordance with a moving motion, and therefore, the problem is posed in an measurement accuracy.
Further, although JP-UM-A-2-612 (page 1, FIG. 4, FIG. 5) is constituted to change a processing of calculating the step of numbers in accordance with a kind of a moving motion, the kind of the moving motion is set by an external operation, and therefore, a problem that the operation becomes complicated is posed.
It is a problem of the invention to dispense with an operation of selecting a measuring mode and enabling to measure the number of steps highly accurately when the number of steps is measured in walking and in running.